Clyde Gateway Pilot 3D Geological and Groundwater Model
2
Citation
0
Reference
20
Related Paper
Citation Trend
Abstract:
This report describes the Clyde Gateway Pilot 3D geological model (superficial deposits, bedrock) and groundwater model (recharge and groundwater flow) which covers 1:10,000 scale Ordnance Survey sheets NS66SW, NS66NW and NS56SE. The groundwater model considers a broader area in general, and also, for practical purposes, a detailed consideration of NS56NE, based on available hydrogeological data. Therefore, the models, and report, address not only the Clyde Gateway area itself, but a larger area which includes for example the alignments of the M74 Extension and East End Regeneration Route.
The report provides background information to the model user including brief geological descriptions, model construction methods, uncertainty factors, limitations and a helpful 3D model user manual.Keywords:
Bedrock
Gateway (web page)
Geological survey
3d model
Groundwater model
Cite
Cite
Citations (22)
A preliminary 3D model of post-Permian bedrock geology in the Vale of Pickering, North Yorkshire, UK
The British Geological Survey (BGS), together with a number of partners is undertaking an independent environmental monitoring programme to characterise baseline conditions across the Vale of Pickering in North Yorkshire, in the vicinity of a site close to Kirby Misperton (Third Energy, KM8) proposed for shale-gas exploration and production. The monitoring will include measurement of: water quality (groundwater and surface water), seismicity, ground motion, air quality including radon, and soil gas. The programme aims to establish the environmental baseline before any shale-gas explorations begin.
This report presents the results of a desk study to develop an initial summary of the post-Permian bedrock geology across the Vale of Pickering. It is a component and specific deliverable of the environmental baseline project. The bedrock deposits form a number of shallow aquifers that are used locally for drinking water supply and agriculture. A separate report considers the superficial geology.
The geological information in this report will form the basis for identifying aquifer dimensions and configurations, groundwater flow paths and potential contaminant migration pathways, as well as determining optimum locations for sampling and monitoring. It will also provide information to support the locating of new borehole infrastructure (suitable for groundwater sampling and seismometers) and will underpin the interpretation of acquired hydrogeochemical data.
Bedrock
Baseline (sea)
Cite
Citations (0)
The Bromsgrove Sandstone aquifer is over-abstracted. This has resulted in a long-term fall in
groundwater levels, the reduction or loss of baseflow and the derogation of surface water
features. To support flows in Battlefield Brook (a BAP site and notable amenity feature in
Bromsgrove), Bow Brook (BAP site) and water levels in Hewell Grange Lake (SSSI), four
alleviation of low-flow (ALF) boreholes are operated (one by the Environment Agency and three
by Severn Trent Water). These ALF boreholes were installed as short term measures, prior to the
implementation of a long-term solution to reduce the impacts of groundwater abstraction on
surface water features which is under discussion between the water company and the
Environment Agency.
In 2001 an existing groundwater model of the Bromsgrove Sandstone aquifer (developed by
Birmingham University in 1990) was adopted and updated as part of the Environment Agency
Midlands Region Groundwater Modelling Strategy. However, monitoring data collected since
2002 has shown that this groundwater model does not accurately simulate groundwater flows
and levels in critical areas. The Bromsgrove aquifer groundwater modelling project aims to
develop a new groundwater model that will be used to determine a more optimal groundwater
abstraction regime which benefits the surface water environment, with the minimum of overall
groundwater abstraction reduction and affordability.
The British Geological Survey (BGS) was contracted to undertake Environment Agency Task
1.1 of the Bromsgrove aquifer groundwater modelling study, namely the production of a three
dimensional geological model of the investigation area. The model was specified to cover the
outcrop of the Bromsgrove Sandstone Formation, the outcrop of the Clent Formation to the north
and the confined Sherwood Sandstone Group to the west. The geographical limits of the area are
approximately Droitwich Spa and Astwood Bank in the south (Northing 261550) and Rubery in
the north (Northing 279560), Elmley Lovett (Easting 387134) in the west and Redditch (Easting
405456) in the east. The outline of the project area is given in Figure 1. The 3D geological model
will be used in a concurrent Task (Task 1.2) to develop the conceptual model of groundwater
flow between the principal formations of the Bromsgrove Sandstone aquifer system, as well as
providing the geometrical information for building the groundwater model (Task 2).
This report outlines the methods used in the BGS 3D geological visualisation work and provides
a brief summary of the stratigraphy, facies relationships and structure of the bedrock geology.
Much of the information in the report has not been published before, and results from an
extensive reinterpretation of existing borehole lithological descriptions and geophysical logs.
The model integrates information from BGS 1:50000 geological sheets (E167 Dudley, E168
Birmingham, E182 Droitwich and E183 Redditch), borehole descriptions derived from core or
cuttings, geophysical logs and NEXTMap digital terrain data. Published information on the
regional geological framework was also incorporated into the model (e.g. Old et al., 1991, Old et
al. 1987, Powell et al. 2000).
Groundwater model
Cite
Citations (0)
This report summarises the results of a collaborative study jointly funded by the North-west
Region of the Environment Agency (the Agency) and the British Geological Survey (BGS).
BGS was commissioned to carry out a geological and hydrogeological characterisation of the
superficial deposits of the Central Manchester and Salford district as a contribution to a regional
groundwater study of the Manchester and Cheshire aquifer being undertaken by the Agency.
The overall objective of the study was to use a three-dimensional (3D) model of the superficial
deposits to examine potential groundwater-surface water interactions. By integrating the modern
1:10,000 geological map with sub-surface (site investigation) information, the relationships
within the quaternary deposits have been characterised and potential hydrogeological pathways
between the surface water bodies and the deeper sandstone aquifer were identified.
The work has shown that the Permo-Triassic aquifer is largely protected by glacial clay and silt
deposits. However, the distribution and thickness of these deposits varies greatly across the area
and hydraulic windows have been identified in the lowland areas where recharge may occur.
Extensive sandy outwash sheet deposits, which are locally in contact with the underlying Permo-
Triassic aquifer, offer the potential for lateral migration of groundwater in perched aquifers.
Large areas and thicknesses of man-made material have been described and modelled and these
could form potential sources of pollution, especially where they are in direct contact with the
major aquifer or perched aquifers.
The work involved four main tasks:
• Determining the geometry, composition and spatial distribution of the principal
superficial (drift) deposits;
• Identifying potential pathways for groundwater movement through the drift;
• Constructing a suite of land-use maps to help assess the locations of potentially
contaminative activities;
• Constructing a domain-based aquifer vulnerability model.
Outputs of the study include:
An attributed model of the superficial geology that can be interrogated at any x,y,z location
An indication of potential flowpaths along bespoke sections through the 3D model and in plan
view along the major superficial aquifers
A novel hydrogeological domains map, based on established domain principals, but derived by
computation from the 3D model
A detailed dataset on past contaminative land use and the distribution, thickness and variation
of the main areas of artificial ground
All data delivered digitally (CD-ROM) and as a printed report with maps.
Silt
Outwash plain
Cite
Citations (1)
Cite
Citations (1)
Aquifer properties
Groundwater model
Syncline
Cite
Citations (77)
The British Geological Survey (BGS), together with a number of partners is undertaking an
independent environmental monitoring programme to characterise baseline conditions in the
south Fylde east of Blackpool in an area proposed for shale-gas exploration and production. The
monitoring will include measurement of: water quality (groundwater and surface water),
seismicity, ground motion, air quality including radon, and soil gas. The programme aims to
establish the environmental baseline before any shale-gas explorations begin.
This report presents the results of a desk study to develop an initial summary of the post-
Carboniferous bedrock geology of the south Fylde. It is a component and specific deliverable of
the environmental baseline project. The bedrock deposits form a number of shallow aquifers that
are used locally for drinking water supply and agriculture. A separate report considers the
superficial geology.
The geological information in this report will form the basis for identifying aquifer dimensions
and configurations, groundwater flow paths and potential contaminant migration pathways, as
well as determining optimum locations for sampling and monitoring. It will also provide
information to support the locating of new borehole infrastructure (suitable for groundwater
sampling and seismometers) and will underpin the interpretation of acquired hydrogeochemical
data.
Bedrock
Baseline (sea)
Geological survey
Cite
Citations (0)
The conceptual groundwater model is heavily dependent on the geological framework which is used to defi ne the aquifer being studied.In the past, two-dimensional datasets such as geological maps and cross-sections were used in coordination with site-specifi c point data to build a conceptual understanding at the site or catchment scale.This is then simplified and it is this simplifi ed version which is used to build the framework for the numerical groundwater fl ow model.Due to the way the geological framework model and the conceptual groundwater model were generated they could not be viewed together; this inevitably led to a signifi cant loss of information and understanding.With the current rapid developments in 3D modelling software and the increasing availability of digital geological data it is now possible to produce detailed 3D geological models of complex aquifer sequences.In this paper we will use two case studies (Chalk aquifer of the London Basin and the Jurassic limestone aquifer of the Cotswolds) to demonstrate that by developing a detailed 3D geological model signifi cant benefi ts are gained in the understanding and development of the conceptual groundwater model.
Conceptual model
Cite
Citations (21)
Cite
Citations (53)
Groundwater models are useful in improving knowledge of groundwater flow processes, both for testing existing hypotheses of how specific systems behave and predicting the response to various environmental stresses. The recent advent of highly detailed three-dimensional (3D) geological-framework models provides the most accurate representation of the subsurface. This type of modelling has been used to develop conceptual understanding of groundwater in the complex Quaternary deposits of Glasgow, Scotland (UK). Delineating the 3D geometry of the lithostratigraphical units has allowed the most detailed conceptualisation of the likely groundwater flow regime yet attempted for these superficial deposits. Recharge and groundwater flow models have been developed in order to test this conceptual understanding. Results indicate that the direction of groundwater flow is predominantly convergent through the permeable, relatively thick Quaternary deposits of the Clyde valley towards the River Clyde, which runs through Glasgow, with some indication of down-valley flow. A separate nearby system with thick and potentially permeable Quaternary deposits, the Proto-Kelvin Valley, may also be a significant conveyor of groundwater towards the River Clyde, although the absence of local data makes any conclusions conjectural. To improve the robustness of the current model there is a need for an overall increase in good quality groundwater-level data, particularly outside central Glasgow. A prototype groundwater-monitoring network for part of Glasgow is an encouraging development in this regard. This would allow the development of a time-variant groundwater model which could be used to study future modelling scenarios.
Groundwater model
Cite
Citations (27)